Key races to watch in 2014

34 Democratic seats not up for election in 201451 seats for majority30 Republican seats not up for election in 2014

7 Democratic governors not up for election in 20147 Republican governors not up for election in 2014

Updated August 7, 2014

As Election Day 2014 approaches, Republicans hold a 234-201 majority in the 435-member House of Representatives. (There are currently two vacancies, but for balance-of-power purposes, CNN considers both of those seats –New Jersey’s 1st District and North Carolina’s 12th District – to be safely Democratic.)

The Democrats need a net gain of 17 seats to capture the majority. Unfortunately for them, as with the Senate they are swimming against the historical and mathematical tide.

First, the President’s party rarely gains seats in the sixth year of an administration. Second, while all 435 seats are technically up, gerrymandering and other factors have combined to ensure that only a small sliver of those seats are actually competitive.

Of the 50 seats that CNN currently considers to be the most competitive, 26 are currently Democratic and 24 are Republican. Even if Democrats manage to hold all of their vulnerable seats, they’d still have to win the overwhelming majority of vulnerable Republican seats to capture the majority.

In other words, Democrats face very long odds in their quest for a House majority.

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Updated September 22, 2014

Democrats have held the majority in the Senate for almost eight years, but as Election Day 2014 approaches Republicans are confident that math and history are on their side.

Democrats head into the election with a 55-45 advantage; Republicans need a net gain of six seats to win a majority. Unfortunately for the Democrats, they have to defend 21 of the 36 seats up for grabs this year. Making matters worse for the Democrats is the fact that seven of their seats up this year are in states carried by Mitt Romney in 2012.

Democrats also have to contend with the electorate’s six-year itch. The party occupying the White House in the sixth year of a presidential administration almost invariably loses seats in Congress.

CNN currently calculates that a total of 9 Democratic seats up this year are at risk: Alaska, Arkansas, Colorado, Iowa, Louisiana, Michigan, New Hampshire, North Carolina and West Virginia.

Two more Democratic seats — in Montana and South Dakota — are already virtually conceded to the GOP.

As for the Republicans, CNN currently calculates that two vulnerable incumbents are up this year: Senate Minority Leader Mitch McConnell of Kentucky and Kansas Sen. Pat Roberts. The race for the open GOP seat in Georgia – currently held by retiring Sen. Saxby Chambliss – could also be competitive in November.

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Updated September 29, 2014

Republicans currently hold a 29-21 edge in the nation’s 50 governorships. But that advantage puts the GOP on the defensive this year, as Republicans prepare to defend 22 governorships in November compared to only 14 for Democrats.

Democrats can also take solace from the fact that races for governor are generally not closely tied to a party’s political fortunes in Washington. Democratic gubernatorial candidates have less to fear from voter exhaustion with President Barack Obama than their counterparts in Senate and House races.

CNN’s current 2014 analysis shows that half of this year’s 36 races for governor could be competitive. Incumbent Republican governors are in tossup races in five states: Florida, Kansas, Maine, Michigan, and Wisconsin. Incumbent Republicans in four more states – Georgia, Iowa, New Mexico and South Carolina – appear more secure, but could end up in tighter races by Election Day.

Pennsylvania Gov. Tom Corbett, also a Republican, faces an uphill climb in his fight for re-election this fall.

The race for Arizona’s governorship, now held by retiring Republican Jan Brewer, could potentially prove competitive as well. And while the GOP should end up on top in bright red Texas, that race is likely to create a lot of sparks with Democratic state Sen. Wendy Davis – previously at the epicenter of an abortion-related media storm – as her party’s nominee.

On the Democratic side, there are three governorships currently considered tossups: Connecticut, Illinois and Arkansas, where incumbent Gov. Mike Beebe can’t run again. If the GOP gets lucky, races for governorships now held by Democrats could also potentially become more competitive in Colorado, Massachusetts and Rhode Island.